Oilfield operations, such as surveying, drilling, wireline testing, completions and production, are typically performed to locate, gather, store and transport valuable downhole fluids. As shown in FIG. 1A, surveys are often performed using acquisition methodologies, such as seismic scanners to generate maps of underground structures. These structures are often analyzed to determine the presence of subterranean assets, such as valuable fluids or minerals. This information is used to assess the underground structures and locate the formations containing the desired subterranean assets. Data collected from the acquisition methodologies may be evaluated and analyzed to determine whether such valuable items are present, and if they are reasonably accessible.
A formation is a distinctive and continuous body of rock that it can be mapped. Spaces between the rock grains (“porosity”) of a formation may contain fluids such as oil, gas or water. Connections between the spaces (“permeability”) may allow the fluids to move through the formation. Formations with sufficient porosity and permeability to store fluids and allow the fluids to move are known as reservoirs. A structure is a geological feature that is created by deformation of the Earth's crust, such as a fold or fault, a feature within the rock itself (such as a fracture) or, more generally, an arrangement of rocks. The above definitions are taken from Schlumberger's Oilfield Glossary (www.glossary.oilfield.slb.com), but in the industry, the terms formation and structure may be loosely used synonymously.
The complex operations of drilling and completing wells are well known by those of skill in the art and the description here is a simplified view. As shown in FIG. 1B-1D, one or more wellsites may be positioned to penetrate the underground structures to gather valuable fluids from the subterranean reservoirs. The wellsites are provided with tools capable of locating and removing hydrocarbons from the subterranean reservoirs. As shown in FIG. 1B, drilling tools are typically advanced from the oil rigs and into the earth along a planned path to access the reservoirs containing the valuable assets. Fluid, such as drilling mud or other drilling fluids, is pumped down the inside the drilling tools, and out of a drilling bit at the bottom of the drilling tools. The drilling bit is used to grind up the earth. After leaving the drilling bit, the drilling fluids flow between the outside of the drilling tools and the inside of the wellbore and back up to the surface. The drilling fluids bring the ground earth to the surface and hold back fluids from formations from prematurely entering the wellbore. During the drilling operation, the drilling tools may include components to perform downhole measurements to investigate the formations encountered. The drilling tools may be used to take samples of the formations, such as core samples. At various points in the drilling, the drilling is stopped and the drilling tools removed from the well. At such a point, as shown in FIG. 1C, after the drilling tools are removed, a wireline tool is deployed into the wellbore to perform additional downhole testing. Wireline tools may also be used to take samples of the formations or to sample the fluids in the formations. At such points, as is known in the art, after any desired wireline tools are run and removed, steel casing may be run into the well to depth and cemented into place to shore up the wellbore and to protect the formations through which the wellbore has passed. The drilling continues in the manner until the desired total depth is reached.
After the drilling operation is complete, the well may then be prepared for production. As shown in FIG. 1D, wellbore completions equipment is deployed into the wellbore to complete the well in preparation for the production of fluid therethrough. Fluid is allowed to flow from downhole reservoirs, into the wellbore and flows to the surface, generally through tubing and their completion equipment positioned in the wellbore. At the surface, the fluids flow through a wellhead and Christmas tree and into a production line. Production facilities are positioned at surface locations to collect the hydrocarbons from the wellsite(s) and to separate and direct fluids from the wells. Various equipment may be positioned about the oilfield to monitor oilfleld parameters and/or to manipulate the oilfield operations,
During the oilfield operations, data is typically collected for analysis and/or monitoring of the oilfield operations. Such data may include, for example, subterranean formation, equipment, historical and/or other data. Data concerning the subterranean formation is collected using a variety of sources. Such formation data may be static or dynamic. Static data relates to formation structure and geological stratigraphy, which defines the geological structure of the subterranean formation. Dynamic data relates to fluids flowing through the geologic structures of the subterranean formation. Such static and/or dynamic data may be collected to learn more about the formations and the valuable assets contained therein.
Sources used to collect static data may be seismic tools, such as a seismic truck that sends compression waves into the earth as shown in FIG. 1A. These waves are measured to characterize changes in the density of the geological structure at different depths. This information may be used to generate basic structural maps of the subterranean formation. Other static measurements may be gathered using core sampling and well logging techniques. Core samples are used to take physical specimens of the formation at various depths as shown in FIG. 1B. Well logging involves deployment of a downhole tool into the wellbore to collect various downhole measurements, such as density, resistivity, etc., at various depths. Such well logging may be performed using, for example, the drilling tool of FIG. 1B and/or the wireline tool of FIG. 1C. Once the well is formed and completed, fluid flows to the surface, preferably using production tubing as shown in FIG. 1D. As fluid passes to the surface, various dynamic measurements, such as fluid flow rates, pressure and composition may be monitored. These parameters may be used to determine various characteristics of the subterranean formation.
Sensors may be positioned throughout the oilfield to collect data relating to various oilfield operations. For example, sensors in the wellbore may monitor fluid composition, sensors located along the flow path may monitor flow rates and sensors at the processing facility may monitor fluids collected. Other sensors may be provided to monitor downhole, surface, equipment or other conditions. The monitored data is often used to make decisions at various locations of the oilfield at various times. Data collected by these sensors may be further analyzed and processed. Data may be collected and used for current or future operations. When used for future operations at the same or other locations, such data may sometimes be referred to as historical data.
The processed data may be used to predict downhole conditions, and make decisions concerning oilfield operations. Such decisions may involve well planning, well targeting, well completions, operating levels, production rates and other configurations. Often this information is used to determine where to drill new wells, how to re-complete or stimulate existing wells, or alter wellbore production.
Data from one or more wellbores may be analyzed to plan or predict various outcomes at a given wellbore. In some cases, the data from neighboring wellbores, wellbores into the same formations or wellbores with similar conditions or equipment is used to predict how a well will perform. There are usually a large number of variables and large quantifies of data to consider in analyzing wellbore operations. It is, therefore, often useful to model the behavior of the oilfield operation to determine the desired course of action. During the ongoing operations, the operating conditions may need adjustment as conditions change and new information is received.
Techniques have been developed to model the behavior of geological structures, downhole reservoirs, wellbores, surface facilities as well as other portions of the oilfleld operation. Examples of modeling techniques are shown in Patent/Application/Publication Nos. U.S. Pat. No. 5,992,519, WO2004/049216, WO1999/064896, U.S. Pat. No. 6,313,837, US2003/0216897, US2003/0132934, US2005/0149307, and US2006/0197759. Typically, existing modeling techniques have been used to analyze only specific portions of the oilfield operation. More recently, attempts have been made to use more than one model in analyzing certain oilfield operations.
See, for example, Patent/Application/Publication Nos. U.S. Pat. No. 6,980,940, WO2004/049216, US2004/0220846, and US Ser. No. 10/586,283.
Techniques have also been developed to predict and/or plan certain oilfield operations, such as drilling operations. Examples of techniques for generating drilling plans are provided in Patent/Application/Publication Nos. US2005/0236184, US2005/0211468, US2005/0228905, US/2005/0209886, and US2005/0209836. Some drilling techniques involve controlling the drilling operation. Examples of such drilling techniques are shown in Patent/Application Nos. GB2392931 and GB2411669. Other drilling techniques seek to provide real-time drilling operations. Examples of techniques purporting to provide real time drilling are described in Patent/Application Nos. U.S. Pat. No. 7,079,952, U.S. Pat. No. 6,266,619, U.S. Pat. No. 5,899,958, U.S. Pat. No. 5,139,094, U.S. Pat. No. 7,003,439, and U.S. Pat. No. 5,680,906.
A company may amass a large amount of data in a variety of data sources when collecting data at a wellsite as described above. Thus, Information Lifecycle Management (ILM) has become a critical process for companies involved in the processing and storage of data related to oilfield operations. Information related to this data must be accessible and cataloged to allow for rapid processing of information and to reduce redundancy of information.
Typically, a company has a number of data sources they wish to manage. Additionally, the company may wish to track processes utilizing or affecting those data sources. On a smaller scale, these data sources and processes may be tracked in a simple list that is shared throughout the company. In such cases, technical personnel are able to be familiar with all the data sources and processes such that they can be consulted to locate a particular data source or process.
As the number of data sources and processes increase, a more formal method may be required to keep track of the information. A common way of tracking this information is to through the use of a searchable directory of all the data sources. In this scenario, each data source is associated with metadata, describing its contents and uses. For example, metadata for a data source could specify: the origin of the data in the data source, the attributes of the data source, when the metadata was last updated, and any processes that use the data source. A user can search the directory to find data sources meeting specific criteria. The metadata returned by a search may be used to facilitate information management.
Typically, directories of metadata are searchable based on key words and return a list of entries based on the search inputs. A user may then browse the results to see specific details about a particular data source. The directory may also provide groups based on classification of data contained in the data sources. These groups typically act as filters to view all data sources of a certain classification.